We propose to continue our examination of maternal mRNA stored in the oocytes of giant moths. Particular emphasis will be placed on determining mechanisms which prevent translation before the fertilization of the egg. Studies to date reveal that oocyte mRNA is "capped" at the 5' end by guanosine, but that mRNA extracted from the developing embryo is capped by 7-methylguanosine. We will test the translatability of these two types of message in a cell-free protein synthesizing system using an inhibitor of methylation, s-adenosyl homocysteine. If oocyte message is untranslated under these circumstances, we will attempt to extract and purify mRNA methylases from oocytes and embryos to determine why oocyte message is not methylated. We will also examine the proteins associated with mRNA to determine whether or not they play a role in preventing methylation or translation. We will also examine the localization of poly (A) positive RNA in sections of eggs using in situ hybridization methods employing labeled poly-U.